Synthetic turf surface



- My 19, 1970 J. VINICKI 3,51

SYNTHETIC TURF SURFACE Filed Jan. 2, 1968 INVENTOR. JOHN VINI CK IATTORNEY United States Patent M 3,513,061 SYNTHETIC TURF SURFACE JohnVinicki, Decatur, Ala., assignor to Monsanto Company, a corporation ofDelaware Filed Jan. 2, 1968, Ser. No. 695,189 Int. Cl. D03d 27/00 U.S.Cl. 161--21 Claims ABSTRACT OF THE DISCLOSURE A synthetic turf isdisclosed which is particularly useful as a golf green. The turf is awoven fabric having cut thermoplastic monofilament ribbons extendingfrom a base. A portion of the ribbons are of one length and theremainder are at least twice as long. The longer ribbons have a curvedportion which simulates natural grass. The ribbons have a denier of300-1200, a width of 0.01"0.3" and a thickness of 0.001" to 0.003".

The method of making the same comprises fabricating a carpet structurehaving a backing from which extends a plurality of courses of loops of asynthetic filament, the loops being positioned in rows extendingtransverse to the courses. A first row of loops is severed near the tipsthereof and a second row of loops adjacent to the first row is pulled toremove from the backing that portion of each filament extending to thepoint of severing in the first row. The severing and pulling steps arerepeated sequentially along the carpet to transform it from a loop to acut pile carpet.

This invention relates to synthetic turf surfaces and more particularlyto simulated-grass carpeting suitable for outdoor recreational purposes.

It is known to make simulated-grass carpeting or synthetic turf forrecreational uses such as golf greens, etc. Conventionally, thesesimulated turf surfaces include a backing from which extends a pluralityof filaments simulating grass. One of the biggest objections to knownmaterials of this type is that ball roll on such a surface is not alwaystrue. For example, a golf ball stroked on such a surface will deviate ordrift from a straight line path as it slows to a stop unless it isstroked along a line parallel to the warp direction. This is, of course,undesirable since the golfer cannot depend upon the ball to travel alonga straight line.

In addition, existing simulated turf surfaces do not decelerate golfballs at the same rate as natural turf. Generally, conventionalsynthetic turf is only /2 to as effective as natural turf indecelerating a golf ball. In other words, a golf ball stroked with agiven force, will travel 2 to 3 times as far on conventional simulatedturf surfaces as it will on natural turf. This is another disadvantageof conventional synthetic turf. With these problems in mind, one of theobjects of this invention is to provide a novel and improved syntheticturf.

Another object of this invention is to provide a simulated turf or grassrecreational surface which does not have a tendency to deflect a rollingball from a straight line path.

A further object of this invention is to provide a simulated-grassrecreational surface having the appearance of natural grass.

Still another object of this invention is to provide a synthetic turfhaving ball deceleration characteristics similar to natural turf.

A further obpect of this invention is to provide a simulated-grassrecreational surface which has a backing from which extends a pluralityof synthetic filaments in ribbon form, portions of the syntheticfilaments having a molec- Patented May 19, 1970 ular orientation whichvaries from one side of the filament to the other.

One embodiment of the present invention contemplates making asimulated-grass recreational urface or synthetic turf by weaving a looppile carpet structure, the loops of said carpet structure being made ofa synthetic monofilament having a fiat, ribbon-like configuration. Afirst row of loops is out near the tips thereof and then tension isapplied to an adjacent row of filaments to pull out the cut ends out ofthe backing layer. These two steps are repeated alternately along thecarpet to provide a cut pile carpet having pile filaments of twodifferent lengths.

Other objects and advantages of the invention will become apparent whenthe following detailed description is read in conjunction with theappended drawing, in which FIG. 1 is a perspective view of a swatch ofthe synthetic tur'f or recreational surface of the present invention,

FIG. 2 is an enlarged cross-sectional view showing the manner in whichthe looped pile is cut and pulled out of the backing layer to provide acut pile carpet,

FIG. 3 is an enlarged view of a conventional wire used in a carpet loomshowing the knife utilized to cut the looped pile,

FIG. 4 is a perspective view of a carpet loom wire with the cuttingblade removed, and

FIG. 5 is an enlarged cross-sectional view showing the manner in whichthe pile filaments are pulled across the sharp corners of the wire asthe wire is withdrawn from the row of loops.

Referring now in detail to the drawing, there is shown a backing layer11 from which extends a plurality of synthetic filaments to form asimulated-grass recreational surface or turf 12. The backing layer 11 isa woven structure which is fabricated on a carpet loom in such a mannerthat picks 13 hold filament loops 16 in an upright position. Forclarity, the warp threads are omitted from the drawing. This type ofcarpet weaving is conventional and may be done on a Wilton or Velvetloom.

The filaments making up the loops 16 are extruded syntheticthermoplastic monofilaments in ribbon form and have a denier within therange of 300 to 1200, a width in the range of 0.01-0.3 and a thicknessin the range of 0.001-0003". The filaments, which are generally flat andribbonlike to simulate natural grass and possess suitable bendingproperties, may be pigmented green to simulate the color of grass. Othercolors may be used for special effects.

Some of the thermoplastic compositions which may be used for making theribbon are nylon, polypropylene, acrylic, polyester, etc. Of these,nylon is preferred.

The monofilament ribbons run along the backing layer in courses as shownin FIG. 2 with the loops 16 being arranged in rows perpendicular to thecourses. At this stage of the fabrication the recreational surface hasthe construction and configuration of a woven loop pile carpet.

The wires used in the weaving of this recreational surface are thoseconventionally used in the making of cut pile woven carpets with theexception that the knives utilized for cutting the loops are removedfrom half of the wires (i.e., every other wire). FIG. 3 shows theconventional wire 19 which has an enlarged head 20 and a cutting blade21. When the wire 19 is pulled along the row of loops to remove ittherefrom, the blade 21 will sever each loop at or near the tip thereofto convert the carpet from a loop pile carpet to a cut pile carpet.

FIG. 4 shows a wire 24 having an enlarged head 25 but no cutting blade21. The purpose of this wire 24 will be explained hereinafter.

The wires 19 and 24 are used alternately in fabricating the recreationalsurface. In other words, as the carpet is woven each wire 19 will :bepositioned between two wires 24 and each wire 24 will be positionedbetween two wires 19. A number of these wires are utilized in weavingthe carpet and as each new loop 16 is formed the wire most remote fromthat loop is pulled out of its row of loops in a well known manner.

The first row of loops is formed on one of the wires 19 with a blade 21while the second row of loops is formed on one of the wires 24 without acutting blade. When the wire 19 in the first row of loops is withdrawnthe blade 21 severs the row of loops near the tips thereof. Then whenthe wire 24 (without a blade) is withdrawn from the next row of loopsthe enlarged head 25 applies tension to the loops in this row to pullout of the backing layer that portion of each of the filaments extendingto the cut made in the first row of loops. The third wire, which has ablade 21, is then withdrawn and the blade 21 severs the loops in thisrow at the tips thereof. Then when the fourth wire which has no blade iswithdrawn, it pulls out that portion of each of the filaments extendingto the cut in the preceding row. These steps of severing and pulling arerepeated sequentially on the successive rows of loops.

It can readily be seen that the cutting and pulling operations performedsuccessively along the carpet as described hereinabove result in asynthetic turf having a cut pile of two different lengths. The length ofthe shorter cut pile filaments 26 will be substantially equal in lengthof the looped pile 16 prior to the cutting. The length of the longer cutpile filaments 27 will be (measured along the filament) approximatelytwo to three times the length of the shorter filament 26. While theshorter filament 26 will have a fairly straight configuration, thelonger filament 27 will have a configuration similar to that shown inFIG. 2. Each of the longer filaments 27 has a curved portion 29 and afairly sharp bend or elbow 30. The bend or elbow 30 is caused bydeformation of the filament 27 which is caused as tension is applied tothe filament 27 as it is held by the pick 13.

The curved portion 29 is a result of pulling the filament 27 undertension over the sharp edges of the wire 24. The wire 24 is thin and hasrelative sharp corners. As the enlarged head 25 passes through the loopit applies tension to the filament 27 which, as it pulls out of thebacking layer, is drawn across the sharp edges of the head 25 undertension. This effects a change in the molecular orientation of the sideof the filament 27 in contact with the sharp edges of the wire 24. Sincethe molecular orientation on one side of the filament is different fromthat on the other side, the filament will tend to bend or curl asillustrated in FIG. 2.

It is not quite understood why but a golf ball stroked across thissurface travels along a straight line with no deviation therefrom as theball comes to a stop. Perhaps it is because the longer filaments 27,while retaining basically the configuration shown in FIG. 2, tend toassume random positions (rather than the orderly positions shown in FIG.2) so that the same resistance is offered to the ball regardless of itsdirection of travel relative to the warp of the fabric. Of course, ifthis fabric is utilized 4 on a slope the force of gravity will have someeffect on the direction of ball travel. However this direction of travelwill not be influenced or changed because of the nature of the surface12.

A further advantage of this synthetic turf is that the ball decelerationrate on this turf is very similar to that of natural turf. Onconventional synthetic turf a golf ball will roll several times as far,when impelled by given force, as it will on natural turf. Thisundesirable characteristic is overcome in the present invention.

It is to be understood that the embodiment disclosed herein merelyillustrates the invention and that numerous other embodiments can becontemplated without departing from the spirit and scope of theinvention.

What is claimed is:

1. A simulated grass-like woven product comprising a warp and fillbacking layer, and a plurality of synthetic thermoplastic cut pilemonofilament ribbons anchored in the backing layer and extendingtherefrom, said ribbons having a denier in the range of 300 to 1200 anda width at least three times greater than its thickness, a portion ofsaid monofilament ribbons having a predetermined length, with theremainder of said monofilament ribbons having a length at least twice asgreat as said predetermined length and having along at least a portionof the length thereof a molecular orientation which varies from onevalue on one side of said monofilament ribbon to another value on theother side of said monofilament ribbon to thereby impart a curl to eachsaid monofilament ribbon.

2. The product of claim 1 wherein the thermoplastic monofilament ribbonis selected from the group consisting of nylon, polypropylene, acrylicand polyester.

3. The product of claim 2 wherein the thermoplastic monofilament isnylon.

4. The product of claim 1 wherein the ribbons have a width in the rangeof 0.01-0.3 and a thickness in the range of 0.001"-0.003".

5. The product of claim 1 wherein the longer ribbons include a curvedportion connected to an elbow shaped bend which terminates at a cut end.

References Cited UNITED STATES PATENTS 1,319,709 10/1919 Hope 139-4021,319,710 10/1919 Hope 139-402 2,759,495 8/1956 Masland 139-402 XR3,157,557 11/1964 Palmer 161-19 3,332,828 7/1967 Faria et al. 161-213,390,044 6/1968 Malakoff 161-19 3,414,266 12/1968 Mitchell 161-63 XRROBERT F. BURNETT, Primary Examiner R. H. CRISS, Assistant Examiner US.Cl. X.R.

